Process and equipment for secondary environment-friendly recycling of waste solvent

Abstract

The invention provides a process and equipment for secondary environment-friendly recycling of a waste solvent, which are applied to the technical field of production and manufacturing, and are characterized in that the waste solvent of an enameled wire is filtered, the filtered recycled solvent is sampled, the specific proportion of paint resin in the solvent is analyzed, and then the proportion of high-solid-content paint resin needing to be added is calculated according to a measurement result; and mixing the high-solid-content paint resin with the recovered solvent according to the calculated ratio, pumping the high-solid-content paint resin from the bottom of the container by using a circulating pump, and mixing the high-solid-content paint resin with the recovered solvent in an upward spraying manner, so that the high-solid-content paint resin and the recovered solvent are fully mixed to form the low-solid-content paint resin capable of being secondarily utilized. According to the secondary environment-friendly recycling process for the waste solvent, the recycling rate of the waste solvent is increased, the performance of the recycled solvent is ensured by accurately controlling the proportion of paint resin, and the dual requirements of environment protection and economic benefits are met.

Description

Technical Field

[0001] The present application relates to the field of production and manufacturing technology, and in particular to a process and equipment for secondary environmentally friendly recycling of waste solvents. Background Art

[0002] During the production and operation of enameling wire, the enameling machine will inevitably encounter situations such as "wire breakage", "gauge change" and "maintenance". When the above situations occur, the necessary treatment measures are to use solvents to circulate and clean the molds, paint boxes, paint tanks, etc. The waste solvent after solvent cleaning becomes hazardous waste, which can not only fail to play the physical value of the solvent, but also cost a lot of money for professional hazardous waste treatment.

[0003] There are two main ways to deal with waste solvents in the enameled wire industry, both of which have related disadvantages, as follows: 1. Ask a professional hazardous waste company to handle it: Enterprises need to invest a lot of hazardous waste storage management costs, such as sites, containers, personnel, safety and environmental protection facilities, etc., and it is difficult to grasp the timeliness of treatment; it is expensive to ask professional institutions to carry out harmless treatment; the physical value of solvents cannot be utilized, such as dissolving resins and circulating combustion heat energy.

[0004] 2. Use the solvent recovery equipment based on the distillation principle that is available on the market to perform secondary distillation recovery of waste solvents: However, the recycling and processing capacity of this method is general; the use of the solvent recovery equipment is power-consuming and time-consuming, and the safety of the temperature and pressure of the entire distillation process needs to be discussed; and the waste solvent is a mixture, and the distillation range of the fractions is different. Some components of the secondary solvent after redistillation are bound to be missing. The dissolution quality of the recovered solvent is severely discounted and it is difficult to use it directly again. It can only be used as an auxiliary material to be blended with a new solvent, and it is difficult to fully utilize the residual value of the waste solvent.

[0005] Therefore, the prior art lacks an environmentally friendly, efficient, cost-saving device and a treatment process that fully utilizes the combustion calorific value of the waste solvent. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present application provides a process and equipment for the secondary environmentally friendly reuse of waste solvents, which is applied to the field of production and manufacturing technology. By mixing the waste solvents with high-solid paint resins, a low-solid paint resin that can be reused is formed. This low-solid paint resin can be directly used in the enameled wire production process without additional treatment, greatly improving the efficiency of resource utilization.

[0007] In a first aspect, a process for secondary environmentally friendly reuse of waste solvents is provided, wherein the waste solvents of enameled wires are filtered for particulate impurities to obtain a treated recovered solvent containing paint resin; Sampling the recovered solvent to obtain the proportion of the paint resin in the recovered solvent, and calculating the addition amount of the high-solid paint resin according to the proportion of the paint resin; The high-solid paint resin and the recovery solvent are mixed into the cavity according to the added amount, and the high-solid paint resin is extracted from the bottom of the cavity by a circulation pump and sprayed onto the recovery solvent from above, so that the high-solid paint resin is fully mixed with the recovery solvent in the process of penetrating to the bottom, thereby forming a low-solid paint resin that can be reused.

[0008] The present application provides a process for secondary environmental protection of waste solvents, which filters the waste solvents of enameled wires to remove the particulate impurities therein, thereby obtaining a relatively pure recovered solvent containing paint resin; sampling the recovered solvent after filtration, analyzing the specific proportion of the paint resin therein, and then calculating the amount of high-solid paint resin to be added according to the measurement results, and by accurately calculating the amount of addition, the performance of the final product can be guaranteed to meet the requirements; mixing the calculated amount of high-solid paint resin with the recovered solvent, using a circulating pump to extract the high-solid paint resin from the bottom of the container, and mixing it with the recovered solvent by spraying from above, wherein the use of the circulating pump helps to achieve full mixing of the high-solid paint resin and the recovered solvent, improve the mixing efficiency and uniformity, and in the process of the high-solid paint resin penetrating to the bottom of the recovered solvent, the two are fully mixed to form a low-solid paint resin that can be reused. The beneficial effect of this step is that by reusing the waste solvent, the demand for new materials is reduced, while the potential impact of the waste solvent on the environment is reduced, and the recycling of resources is achieved. The process of secondary environmentally friendly recycling of waste solvents not only improves the recycling rate of waste solvents, but also ensures the performance of recycled solvents by precisely controlling the proportion of paint resins, meeting the dual needs of environmental protection and economic benefits.

[0009] Furthermore, the high-solid paint resin, the recovered solvent and the low-solid paint resin satisfy the relationship (a%*m+b%*n) / (m+n)=c%, wherein a% is the proportion of the paint resin in the high-solid paint resin, m is the mass of the high-solid paint resin, b% is the proportion of the paint resin in the recovered solvent, n is the mass of the recovered solvent, and c% is the proportion of the paint resin in the low-solid paint resin.

[0010] The present application provides a process for the environmentally friendly secondary recycling of waste solvents. The weighted average of the mass percentage concentrations of high-solid paint resin, recovered solvent and low-solid paint resin is calculated through the relationship (a%*m+b%*n) / (m+n)=c%, ensuring that the paint resin content in the mixed low-solid paint resin meets expectations. Through precise calculation and control, the effective recycling of waste solvents is achieved, while ensuring that the performance of the final product meets specific requirements. This method not only improves the utilization efficiency of resources, but also reduces environmental pollution, and has significant economic and environmental benefits.

[0011] Furthermore, the proportion of the paint resin in the high-solid paint resin is 40%, the proportion of the paint resin in the recovered solvent is 1%, and the proportion of the paint resin in the low-solid paint resin is 30%.

[0012] The present application provides a process for the environmentally friendly secondary recycling of waste solvents, which achieves effective recycling of waste solvents by accurately calculating and controlling the proportion of paint resin in high-solid paint resin to be 40%, the proportion of paint resin in recovered solvent to be 1%, and the proportion of paint resin in low-solid paint resin to be 30%, while ensuring that the performance of the final product meets specific requirements. This method not only improves the utilization efficiency of resources, but also reduces environmental pollution, and has significant economic and environmental benefits.

[0013] Furthermore, the steps of filtering the waste solvent of the enameled wire for particulate impurities to obtain the treated recovered solvent containing the paint resin include: coarse filtration and fine filtration; The coarse filtration comprises the steps of: using a circulation pump to pump up the waste solvent of the enameled wire, passing it through a filter element, intercepting large particles with a particle size greater than or equal to a first filter aperture, and obtaining the waste solvent after coarse filtration; The fine filtration includes the steps of using a circulating pump to evacuate the waste solvent after coarse filtration, passing it through a filter bag, intercepting small particles and flocs whose particle size is greater than or equal to a second filter aperture, and obtaining a processed recovered solvent containing paint resin, wherein the second filter aperture is smaller than the first filter aperture.

[0014] The present application provides a process for the environmentally friendly secondary recycling of waste solvents, which uses a circulating pump to extract the waste solvent of the enameled wire, and uses a filter element to intercept large particles with a size greater than or equal to the first filter aperture. This step mainly removes larger solid impurities, and then the waste solvent that has been coarsely filtered is extracted again using a circulating pump, and the small particles and flocs with a size greater than or equal to the second filter aperture are intercepted by a filter bag. This step further removes finer impurities to ensure the purity of the recovered solvent. Through these two steps, the waste solvent is filtered twice at different levels, and finally a recovered solvent with higher cleanliness is obtained, which can be used for further reuse or as a raw material for other processes, thereby realizing resource conservation and environmental protection.

[0015] Furthermore, during the coarse filtration and the fine filtration, the circulation filtration time is 4 hours respectively.

[0016] Further, the steps of mixing the high-solid paint resin and the recovery solvent into the cavity according to the added amount, and using a circulating pump to extract the high-solid paint resin from the bottom of the cavity, and spraying it on the recovery solvent from the top, so that the high-solid paint resin is fully mixed with the recovery solvent in the process of penetrating to the bottom, to form a low-solid paint resin that can be reused include: Pour the high-solid paint resin into the bottom of the cavity according to the added amount, and then pour the recovery solvent onto the top of the high-solid paint resin; Inserting the feed port of the circulation pump into the high-solid paint resin, and connecting a spray pipe group to the discharge port of the circulation pump, wherein the spray port of the spray pipe group is located above the cavity; After the circulation pump extracts the high-solid paint resin from the bottom of the chamber, it is sprayed onto the recovery solvent from above through the spray pipe group, so that the high-solid paint resin is fully mixed with the recovery solvent during the process of penetrating to the bottom to form a low-solid paint resin that can be reused.

[0017] In a second aspect, the present application proposes a device for secondary environmentally friendly recycling of waste solvents, the device is applied to any of the above processes, and the device comprises: Filtering device: used to filter the particle impurities in the waste solvent of the enameled wire to obtain the processed recovered solvent containing the paint resin; Calculation device: used for sampling the recovered solvent, obtaining the proportion of the paint resin in the recovered solvent, and calculating the addition amount of the high-solid paint resin according to the proportion of the paint resin; Processing device: used for mixing the high-solid paint resin and the recovery solvent into the cavity according to the added amount, and using a circulating pump to extract the high-solid paint resin from the bottom of the cavity, and spraying it to the recovery solvent from above, so that the high-solid paint resin is fully mixed with the recovery solvent in the process of penetrating to the bottom, so as to form a low-solid paint resin that can be reused.

[0018] Furthermore, the filtering device comprises: A coarse filtering device is used to filter the enameled wire waste solvent, intercept large particles in the enameled wire waste solvent whose particle size is greater than or equal to the first filter aperture, and obtain the waste solvent after coarse filtration; The fine filtering device is used to filter small particles and floccules whose particle size is greater than or equal to the second filtering aperture to obtain the processed recovery solvent containing paint resin.

[0019] Furthermore, the coarse filtration device includes at least a circulation pump and a filter element connected to the circulation pump, the filter element is provided with a first filter hole, and the aperture of the first filter hole is the first filter aperture; the fine filtration device includes at least a circulation pump and a filter bag connected to the circulation pump, the filter bag is provided with a second filter hole, and the aperture of the second filter hole is the second filter aperture.

[0020] Furthermore, the processing device at least includes a cavity, a circulation pump arranged in the cavity, and a spray pipe group connected to the circulation pump, the feed port of the circulation pump extends into the bottom of the cavity, and the spray port of the spray pipe group is located at the upper part of the cavity.

[0021] Beneficial effect: The present application provides a process and equipment for secondary environmentally friendly reuse of waste solvents, which filters the waste solvent of enameled wire to remove the particulate impurities therein, thereby obtaining a relatively pure recovered solvent containing paint resin; sampling the recovered solvent after filtration, analyzing the specific proportion of the paint resin therein, and then calculating the proportion of high-solid paint resin to be added according to the measurement results, and by accurately calculating the amount of addition, the performance of the final product can be guaranteed to meet the requirements; the high-solid paint resin with the calculated proportion is mixed with the recovered solvent, and the high-solid paint resin is extracted from the bottom of the container by a circulating pump, and mixed with the recovered solvent by spraying from above, wherein the use of the circulating pump helps to achieve full mixing of the high-solid paint resin and the recovered solvent, improve the mixing efficiency and uniformity, and in the process of the high-solid paint resin penetrating to the bottom of the recovered solvent, the two are fully mixed to form a low-solid paint resin that can be reused. The beneficial effect of this step is that by reusing the waste solvent, the demand for new materials is reduced, while the potential impact of the waste solvent on the environment is reduced, and the recycling of resources is achieved. The process of secondary environmentally friendly recycling of waste solvents not only improves the recycling rate of waste solvents, but also ensures the performance of recycled solvents by precisely controlling the proportion of paint resins, meeting the dual needs of environmental protection and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A flow chart of a process for secondary environmentally friendly reuse of waste solvents provided in this application.

[0023] Figure 2 The present application provides a coarse filtering device for equipment for secondary environmentally friendly recycling of waste solvents.

[0024] Figure 3 The present application provides a fine filtering device for equipment for secondary environmentally friendly reuse of waste solvents.

[0025] Figure 4 The present application provides a processing device for equipment for secondary environmentally friendly reuse of waste solvents.

[0026] Figure 5 A composition diagram of an enameled wire waste solvent provided in this application.

[0027] Explanation of reference numerals: 1. Coarse filtration device; 2. Fine filtration device; 3. Treatment device; 11. Circulation pump; 12. Filter element; 21. Filter bag; 31. Spray pipe group; 32. Container; 4. Waste solvent of enameled wire; 41. Particulate matter; 42. Paint resin; 5. Recovered solvent; 6. High-solid paint resin. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application usually described and marked in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0029] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first, second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0030] The following disclosure provides many different implementation methods or examples for achieving the purpose of the present invention. In the production of enameled wires, wire breakage, track switching and maintenance often occur. In these cases, solvents are required to clean the molds, paint boxes and paint tanks. However, the waste solvent after cleaning becomes hazardous waste, which can not bring out the actual value of the solvent, and also requires a lot of money for professional treatment. At present, there are two main treatment methods in the industry: one is to entrust a professional hazardous waste company to deal with it, and the other is to use solvent recovery equipment based on the distillation principle for secondary distillation and recovery. However, both methods have obvious defects and cannot meet the actual needs of enterprises. In order to solve this problem, the present application proposes a process and equipment for secondary environmentally friendly reuse of waste solvents.

[0031] For details, please refer to Figures 1 to 5 , a process for secondary environmentally friendly recycling of waste solvents, S1: filtering the enameled wire waste solvent 4 for particulate impurities to obtain a processed recovered solvent 5 containing a paint resin 42; S2: sampling the recovered solvent 5 to obtain the proportion of the paint resin 42 in the recovered solvent 5, and calculating the addition amount of the high-solid paint resin 6 according to the proportion of the paint resin 42; S3: High-solid paint resin 6 and recovery solvent 5 are mixed into the cavity 32 according to the added amount, and the high-solid paint resin 6 is extracted from the bottom of the cavity 32 by a circulation pump 11, and sprayed onto the recovery solvent 5 from above, so that the high-solid paint resin 6 is fully mixed with the recovery solvent 5 in the process of penetrating to the bottom, thereby forming a low-solid paint resin that can be reused.

[0032] In step S1, the enameled wire waste solvent 4 contains at least solid impurities, dissolved paint resin 42 and solvent components, of which only the solid impurities are harmful components that need to be removed. The solid impurities include at least oxide film, mud and sand, and paint scale. Figure 5 .

[0033] Among them, the process first filters the particulate impurities of the enameled wire waste solvent 4 to obtain the treated recovered solvent 5 containing the paint resin 42. The purpose of this step is to remove solid impurities in the waste solvent and lay the foundation for subsequent treatment. The filtration process can adopt a multi-stage filtration system, including coarse filtration and fine filtration, to ensure the purity of the recovered solvent 5.

[0034] In step S2, after obtaining the recovered solvent 5, the proportion of the paint resin 42 in the recovered solvent 5 can be accurately determined by sampling the recovered solvent 5. This data is a key parameter for subsequent processing because it determines the amount of high-solid paint resin 6 that needs to be added. The sampling process can use high-precision analytical instruments, such as gas chromatographs or liquid chromatographs, to ensure the accuracy of the measurement results. Specifically, multiple samplings can be performed during sampling to calculate the average content of the paint resin 42 contained in the recovered solvent 5, thereby reducing the error caused by accidental situations to the calculation results.

[0035] Based on the sampling results, the process of the present application uses a specific calculation method to determine the amount of high-solid paint resin 6 to be added. This calculation process takes into account the existing paint resin 42 content in the recovery solvent 5 and the resin content required for the final target product (low-solid paint resin). Through accurate calculation, it can be ensured that the amount of high-solid paint resin 6 added will neither be excessive to cause waste nor insufficient to reach the target concentration. In step S3, according to the calculated addition amount, the high-solid paint resin 6 and the recovery solvent 5 are mixed into the cavity 32, and the mixing process adopts an innovative circulation pump spraying technology. Taking advantage of the high density of the high-solid paint resin 6, the circulation pump 11 extracts the high-solid paint resin 6 from the bottom of the cavity 32, and then sprays it evenly onto the surface of the recovery solvent 5 through the spraying device located above the cavity 32. This top-down spraying method uses gravity to fully mix the high-solid paint resin 6 with the recovery solvent 5 during the downward penetration process. This method not only ensures the uniformity of mixing, but also significantly improves the mixing efficiency.

[0036] In order to ensure that the high-solid paint resin 6 and the recovered solvent 5 can be fully mixed, the flow rate of the circulation pump 11 should match the size of the chamber 32 and the mixing requirements, the pressure should be sufficient to evenly spray the high-solid paint resin 6, and the material should be resistant to solvent corrosion. A multi-hole nozzle or a rotating spray arm can be used during spraying to ensure a wide and uniform spray coverage area.

[0037] The process of the present application not only solves the problem of waste solvent treatment, but also realizes the efficient use of resources. By mixing the waste solvent with the high-solid paint resin 6, a low-solid paint resin that can be reused is formed. This low-solid paint resin can be directly used in the enameled wire production process without additional treatment, which greatly improves the efficiency of resource utilization. Compared with the prior art, the process of the present application has significant advantages. Compared with the method of entrusting a professional hazardous waste company to handle it, this process greatly reduces the treatment cost and avoids the complexity of hazardous waste storage and management. Compared with the method of recovery using distillation equipment, this process not only has lower energy consumption and higher safety, but also can retain all the components of the solvent to ensure the quality of the recovered product.

[0038] Furthermore, the high-solid paint resin 6, the recovered solvent 5 and the low-solid paint resin satisfy the relationship (a%*m+b%*n) / (m+n)=c%, wherein a% is the proportion of the paint resin 42 in the high-solid paint resin 6, m is the mass of the high-solid paint resin 6, b% is the proportion of the paint resin 42 in the recovered solvent 5, n is the mass of the recovered solvent 5, and c% is the proportion of the paint resin 42 in the low-solid paint resin.

[0039] Among them, in actual operation, the recovered solvent 5 can first be accurately analyzed for components to determine the proportion of the paint resin 42 therein. This can be achieved through analytical methods such as gas chromatography or liquid chromatography; then, according to production requirements, the concentration of the target low-solid paint resin is determined, which may vary according to different application scenarios; next, a high-solid paint resin 6 of appropriate concentration is selected. Usually, a concentration of about 40% is selected, which can ensure sufficient resin content without causing excessive viscosity and being difficult to handle; finally, these data are substituted into the formula to calculate the specific amount of high-solid paint resin 6 that needs to be added. Through this formula, the amount of high-solid paint resin 6 that needs to be added can be accurately calculated to achieve the target low-solid paint resin concentration. This precise calculation method effectively avoids the problems of over-addition or under-addition commonly seen in traditional processes, thereby greatly improving resource utilization efficiency and reducing production costs.

[0040] Further, the proportion of the paint resin 42 in the high-solid paint resin 6 is 40%, the proportion of the paint resin 42 in the recovery solvent 5 is 1%, and the proportion of the paint resin 42 in the low-solid paint resin is 30%.

[0041] Among them, in some specific embodiments, a certain enameled wire production enterprise produces 500 kg of waste solvent every day. After preliminary analysis, the content of paint resin 42 is 1%. The enterprise hopes to process these waste solvents into 30% low-solid paint resin for use in other production links. According to the formula, it can be calculated that about 273.3 kg of 40% high-solid paint resin 6 needs to be added. In this way, not only the waste solvent is fully utilized, but also about 730 kg of low-solid paint resin that can be directly used is produced, which greatly improves the efficiency of resource utilization.

[0042] In another specific embodiment, the application of this formula under different concentration requirements can be demonstrated. For example, a coating manufacturer needs different concentrations of paint resin 42 for different product lines. They may need to process the recovered solvent 5 into three different concentrations of low-solid paint resins of 20%, 25% and 35%. By adjusting the c% value in the formula, we can quickly calculate the amount of high-solid paint resin 6 that needs to be added in each case, thereby flexibly meeting different production requirements.

[0043] Specifically, the present application stipulates that the proportion of paint resin 42 in high-solid paint resin 6 is 40%. When filtering the particulate impurities of the enameled wire waste solvent 4, a detection instrument can be used to detect the solvent in real time until the filtration is completed, so that the proportion of paint resin 42 in the recovered solvent 5 is 1%. The proportion of paint resin 42 in the low-solid paint resin finally formed is 30%. This precise ratio can not only ensure the quality of the final product, but also maximize the use of waste solvents while reducing the use of new materials. The advantage of this ratio method is that it takes into account the material balance of the entire system. 40% high-solid paint resin 6 provides sufficient resin content, which can effectively increase the resin content of 1% low-concentration recovered solvent 5. The final 30% low-solid paint resin is an ideal concentration that can meet subsequent production needs without causing waste of resources.

[0044] Furthermore, the steps of filtering the waste solvent 4 of the enameled wire for particulate impurities to obtain the treated recovered solvent 5 containing the paint resin 42 include: coarse filtration and fine filtration; The coarse filtration comprises the steps of: using a circulating pump 11 to pump up the enameled wire waste solvent 4, passing through a filter element 12, intercepting large particles 41 with a size greater than or equal to a first filter aperture, and obtaining the waste solvent after coarse filtration; The fine filtration includes the steps of using a circulating pump 11 to evacuate the waste solvent after the coarse filtration, passing through a filter bag 21, intercepting small particles 41 and flocs whose size is greater than or equal to the second filter aperture, and obtaining a processed recovered solvent 5 containing a paint resin 42.

[0045] Among them, in the process of secondary environmentally friendly reuse of waste solvents in the present application, filtering the waste solvent 4 of enameled wire for particulate impurities can not only remove solid impurities in the waste solvent, but also lay the foundation for subsequent treatment. However, in actual operation, a single filtering method may be difficult to meet the requirements for the purity of the recovered solvent 5. In order to further improve the filtering effect, the present application proposes a multi-stage filtering system, including two stages of coarse filtration and fine filtration.

[0046] The coarse filtration stage mainly targets larger particles 41 in the waste solvent. In this stage, the circulating pump 11 is used to pump up the waste solvent 4 of the enameled wire, and then pass it through the filter element 12. The filter element 12 is provided with filter holes of a specific aperture, which can effectively intercept large particles 41 with a size greater than or equal to the first filter aperture. This process can not only remove obvious impurities, but also protect the subsequent fine filtration equipment and extend its service life.

[0047] After the coarse filtration, the waste solvent enters the fine filtration stage. In this stage, the circulating pump 11 is also used, but the waste solvent after the coarse filtration is passed through the filter bag 21. The second filter aperture on the filter bag 21 is smaller than the first filter aperture, and can intercept finer particles 41 and flocs. Through these two stages of filtration, a higher purity recovered solvent 5 can be obtained, providing better raw materials for the subsequent reuse process.

[0048] The multi-stage filtration system of the present application is flexible in design and can be adjusted according to actual needs. For example, filter cores 12 and filter bags 21 of different materials and pore sizes can be selected to adapt to different types of waste solvents. The filter core 12 can be made of metal mesh, ceramic or polymer materials, while the filter bag 21 can be made of nylon, polypropylene or polyester fiber. This flexibility allows the process to adapt to the needs of different industries and different production scales.

[0049] Furthermore, during the coarse filtration and fine filtration processes, the circulating filtration time is 4 hours respectively.

[0050] Among them, in order to ensure the filtering effect, the circulating filtration time in the coarse filtration and fine filtration processes of this application is 4 hours. This time setting is based on a large amount of experimental data verification, which can take into account the processing efficiency while ensuring the filtering effect. However, in actual operation, the filtration time can be appropriately adjusted according to the specific situation of the waste solvent. For example, for waste solvents with a lighter degree of pollution, the filtration time can be appropriately shortened; for waste solvents with severe pollution, it may be necessary to extend the filtration time or increase the number of filtrations.

[0051] Further, the steps of mixing the high-solid paint resin 6 and the recovery solvent 5 into the cavity 32 according to the added amount, and using the circulation pump 11 to extract the high-solid paint resin 6 from the bottom of the cavity 32, and spraying it to the recovery solvent 5 from the top, so that the high-solid paint resin 6 is fully mixed with the recovery solvent 5 in the process of penetrating to the bottom, and forming a low-solid paint resin that can be reused include: Pour the high-solid paint resin 6 into the bottom of the cavity 32 according to the added amount, and then pour the recovery solvent 5 onto the high-solid paint resin 6; Insert the feed port of the circulation pump 11 into the high-solid paint resin 6, and connect the spray pipe group 31 to the discharge port of the circulation pump 11, and the spray port of the spray pipe group 31 is located above the cavity 32; After the circulation pump 11 extracts the high-solid paint resin 6 from the bottom of the cavity 32, it is sprayed from above to the recovery solvent 5 through the spray pipe group 31, so that the high-solid paint resin 6 is fully mixed with the recovery solvent 5 during the process of penetrating to the bottom to form a low-solid paint resin that can be reused.

[0052] Among them, in the process of secondary environmentally friendly recycling of waste solvents in the present application, the mixing process of high-solid paint resin 6 and recovered solvent 5 is a key step. In order to further optimize this process, the present application proposes an improved mixing method. This method can not only ensure the uniformity of mixing, but also improve the mixing efficiency, thereby obtaining a higher quality low-solid paint resin.

[0053] Specifically, the mixing method of the present application includes the following steps: First, according to the pre-calculated addition amount, the high-solid paint resin 6 is poured into the bottom of the cavity 32. The design of this cavity 32 takes into account the special needs of the mixing process, including an appropriate height and diameter ratio, and a special internal structure to promote the mixing effect. After the high-solid paint resin 6 is poured in, the recovery solvent 5 is poured on top of the high-solid paint resin 6. This layered pouring method facilitates the subsequent mixing process.

[0054] Next, insert the feed port of the circulation pump 11 into the high-solid paint resin 6. The selection of the circulation pump 11 is crucial, and factors such as its flow rate, pressure and material need to be considered. The flow rate of the pump should match the size of the cavity 32 and the mixing requirements, the pressure should be sufficient to evenly spray the high-solid paint resin 6, and the material needs to be resistant to solvent corrosion. The spray pipe group 31 is connected to the discharge port of the circulation pump 11, and the spray port of the spray pipe group 31 is located above the cavity 32. The design of the spray pipe group 31 is a key point, and a multi-hole nozzle or a rotating spray arm can be used to ensure a wide and uniform spray coverage area.

[0055] After the circulation pump 11 is started, the high-solid paint resin 6 is drawn out from the bottom of the chamber 32 and sprayed evenly from above to the recovery solvent 5 through the spray pipe group 31. This top-down spraying method utilizes the effect of gravity to fully mix the high-solid paint resin 6 with the recovery solvent 5 during the downward penetration process. This method can not only ensure the uniformity of mixing, but also significantly improve the mixing efficiency.

[0056] During the mixing process, the viscosity of the high-solid paint resin 6 and the fluidity of the recovery solvent 5 are parameters that require special attention. In order to ensure adequate mixing, the mixing effect can be optimized by adjusting the speed of the circulation pump 11 and the spraying time. For example, the speed of the circulation pump 11 can be adjusted by frequency conversion control technology to adapt to high-solid paint resins 6 with different viscosities. In addition, multiple spraying cycles can be set, with a certain interval between each cycle, so that the mixture has sufficient time to diffuse and homogenize naturally.

[0057] This method achieves an efficient and uniform mixing process by designing a circulating spray system and accurately controlling the quality of each mixed solvent, providing a reliable guarantee for obtaining high-quality low-solid paint resin. This method not only improves resource utilization efficiency, but also reduces production costs, providing strong support for the sustainable development of the enameled wire industry.

[0058] Please refer to Figures 2 to 5 The present application proposes a device for secondary environmentally friendly recycling of waste solvents, which is applied to any of the above processes and includes: Filtering device: used for filtering the enameled wire waste solvent 4 for particulate impurities to obtain the treated recovered solvent 5 containing the paint resin 42; Calculation device: used for sampling the recovery solvent 5, obtaining the proportion of the paint resin 42 in the recovery solvent 5, and calculating the addition amount of the high-solid paint resin 6 according to the proportion of the paint resin 42; Treatment device 3: used for mixing high-solid paint resin 6 and recovery solvent 5 into the cavity 32 according to the added amount, and using the circulation pump 11 to extract the high-solid paint resin 6 from the bottom of the cavity 32, and spray it to the recovery solvent 5 from the top, so that the high-solid paint resin 6 is fully mixed with the recovery solvent 5 in the process of penetrating to the bottom, so as to form a low-solid paint resin that can be reused.

[0059] The equipment for secondary environmentally friendly recycling of waste solvents in the present application mainly includes three core parts: a filtering device, a calculating device and a processing device 3. These three parts correspond to the three main steps in the process, forming a complete processing system.

[0060] The filtering device is the first step in the entire treatment process. Its main function is to filter the particulate impurities of the enameled wire waste solvent 4 to obtain the treated recovered solvent 5 containing the paint resin 42. The filtering device can adopt a multi-stage filtering system, including coarse filtration and fine filtration. Coarse filtration can use a large-pore filter or a centrifugal separator to remove large particle impurities. Fine filtration can use a filter element provided with activated carbon to further remove tiny particles and some soluble impurities. The design of the filtering device needs to take into account the characteristics of different types of waste solvents, and replaceable filter elements can be used to meet different filtering needs.

[0061] The calculation device is responsible for sampling the recovered solvent 5, obtaining the proportion of the paint resin 42 in the recovered solvent 5, and calculating the amount of high-solid paint resin 6 to be added based on this proportion. The calculation device can be integrated with high-precision analytical instruments, such as a near-infrared spectrometer or a gas chromatograph, to quickly and accurately determine the content of the paint resin 42 in the solvent. At the same time, it also needs to be equipped with a powerful calculation unit and a special algorithm, which can quickly calculate the amount of high-solid paint resin 6 to be added based on the measurement results and the preset target product parameters. In order to improve flexibility, the calculation device can set a variety of recipe modes to meet different production needs.

[0062] The processing device 3 at least includes a circulation pump 11 extending into the bottom of the cavity 32 and a spray pipe group 31 connected to the circulation pump 11. According to the addition amount given by the calculation device, the high-solid paint resin 6 and the recovery solvent 5 are mixed into the cavity 32. The material of the cavity 32 needs to consider corrosion resistance, and stainless steel or special composite materials can be used. The circulation pump 11 in the processing device 3 is a key component, which needs to be able to accurately control the flow and pressure to ensure the uniformity of the mixing process. The selection of the pump needs to take into account the high viscosity characteristics of the high-solid paint resin 6, and a screw pump or a gear pump or other pump type suitable for conveying high-viscosity liquids can be used.

[0063] The spray pipe group 31 is another important component of the processing device 3. It needs to be able to evenly spray the high-solid paint resin 6 onto the surface of the recovery solvent 5. The spray pipe group 31 can adopt a multi-point spray design to ensure that the entire cross-section of the cavity 32 is covered. The selection of the nozzle needs to take into account the characteristics of the high-solid paint resin 6, and a specially designed atomizing nozzle can be used to improve the uniformity of the spraying.

[0064] The equipment for secondary environmentally friendly recycling of waste solvents proposed in this application realizes efficient recycling of waste solvents through precise filtration, intelligent calculation and efficient mixing treatment. This equipment can not only greatly improve the efficiency and quality of waste solvent treatment, but also significantly reduce treatment costs and reduce environmental pollution.

[0065] Further, the filtering device comprises: A coarse filtering device 1 is used to filter the enameled wire waste solvent 4, intercept large particles 41 in the enameled wire waste solvent 4 whose size is greater than or equal to the first filter aperture, and obtain the waste solvent after coarse filtration; The fine filtering device 2 is used to filter small particles 41 and floccules whose size is greater than or equal to the second filtering aperture to obtain the processed recovery solvent 5 containing the paint resin 42.

[0066] Please refer to Figure 2 The design of the coarse filtration device 1 can be in various forms. For example, a metal mesh filter can be used, which has a large surface area and high durability. Another option is to use a multi-layer fiber filter material, which can have a low pressure loss while ensuring the filtering effect. In addition, a centrifugal separator can also be considered as part of the coarse filtration device 1, especially when the waste solvent contains a large amount of suspended particles.

[0067] Please refer to Figure 3 After the coarse filtration, the waste solvent enters the fine filtration device 2. The main goal of this stage is to remove small particles 41 and floccules whose particle size is greater than or equal to the second filter aperture. The design of the fine filtration device 2 needs to be more precise to ensure that the fine impurities that are not removed in the coarse filtration stage can be captured. This step is crucial to ensure the quality of the final recovered solvent 5, because these tiny impurities may affect the subsequent reuse process.

[0068] In order to further improve the filtering effect, the filtering device of the present application adopts a circulation pump 11 in both the coarse filtering and fine filtering stages. In the coarse filtering stage, the circulation pump 11 is connected to the filter element 12, and in the fine filtering stage, the circulation pump 11 is connected to the filter bag 21. This design can not only ensure that the waste solvent maintains a stable flow rate during the filtering process, but also improve the filtering efficiency through repeated circulation.

[0069] Furthermore, the coarse filtration device 1 at least includes a circulation pump 11 and a filter element 12 connected to the circulation pump 11, the filter element 12 is provided with a first filter hole, and the aperture of the first filter hole is a first filter aperture; the fine filtration device 2 at least includes a circulation pump 11 and a filter bag 21 connected to the circulation pump 11, the filter bag 21 is provided with a second filter hole, and the aperture of the second filter hole is a second filter aperture.

[0070] Among them, the filter core 12 is provided with a first filter hole, and its pore size determines the accuracy of coarse filtration. The filter bag 21 is provided with a second filter hole, whose pore size is smaller than the first filter hole, for finer filtration. The filter bag 21 can be made of a polymer material with good chemical stability and mechanical strength. In practical applications, the filter pore size can be adjusted according to the specific waste solvent composition and target product requirements. For example, for waste solvents containing a large amount of paint particles, the first filter pore size can be set to 100 microns and the second filter pore size can be set to 10 microns. For relatively clean waste solvents, the filter pore size can be reduced accordingly to obtain a higher purity recovered solvent 5.

[0071] Furthermore, the processing device 3 at least includes a cavity 32, a circulating pump 11 arranged in the cavity 32, and a spray pipe group 31 connected to the circulating pump 11, the feed port of the circulating pump 11 extends into the bottom of the cavity 32, and the spray port of the spray pipe group 31 is located at the upper part of the cavity 32.

[0072] Please refer to Figure 4 The feed port of the circulation pump 11 is designed to extend into the bottom of the chamber 32, so that the high-solid paint resin 6 can be continuously extracted, even if the liquid level of the high-solid paint resin 6 gradually decreases during the mixing process. This design avoids the problem of pump idling or reduced extraction efficiency, and ensures the continuity and stability of the entire mixing process.

[0073] The spraying ports of the spraying pipe group 31 are cleverly arranged at the upper part of the cavity 32. This arrangement makes full use of the effect of gravity, so that the sprayed high-solid paint resin 6 can evenly cover the entire surface of the recovery solvent 5, and fully contact and mix with the recovery solvent 5 during the falling process. By adjusting the height, angle and distribution of the spraying ports, the mixing effect can be further optimized to ensure that the high-solid paint resin 6 can be evenly dispersed in the recovery solvent 5.

[0074] In order to realize this design, the circulation pump 11 can be a corrosion-resistant centrifugal pump or a gear pump, and its flow rate and pressure need to be accurately calculated and selected according to the size of the chamber 32 and the mixing requirements. The feed pipe of the pump can adopt an adjustable length telescopic pipe to adapt to the requirements of chambers 32 of different heights and different liquid levels.

[0075] The spray pipe group 31 can be designed as a multi-arm structure, with multiple nozzles evenly distributed on each arm to achieve full coverage of the upper space of the entire cavity 32. Or other forms, such as using a fixed grid-shaped spray pipe to form a uniform spray network on the upper part of the cavity 32. The nozzle can be an atomizing or fan-shaped nozzle to obtain a better atomization effect and coverage area.

[0076] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0077] The above description is only an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.

Claims

1. A process for secondary environmentally friendly recycling of waste solvents, characterized in that: Filtering the enameled wire waste solvent (4) for particulate impurities to obtain a treated recovered solvent (5) containing a paint resin (42); Sampling the recovered solvent (5) to obtain the proportion of the paint resin (42) in the recovered solvent (5), and calculating the amount of the high-solid paint resin (6) to be added according to the proportion of the paint resin (42); The high-solid paint resin (6) and the recovery solvent (5) are mixed into the cavity (32) according to the added amount, and the high-solid paint resin (6) is extracted from the bottom of the cavity (32) by a circulation pump (11) and sprayed onto the recovery solvent (5) from above, so that the high-solid paint resin (6) is fully mixed with the recovery solvent (5) during the process of penetrating to the bottom, thereby forming a low-solid paint resin that can be reused.

2. The process for secondary environmentally friendly recycling of waste solvents according to claim 1, characterized in that: The high-solid paint resin (6), the recovery solvent (5) and the low-solid paint resin satisfy the relationship (a%*m+b%*n) / (m+n)=c%, wherein a% is the proportion of the paint resin (42) in the high-solid paint resin (6), m is the mass of the high-solid paint resin (6), b% is the proportion of the paint resin (42) in the recovery solvent (5), n is the mass of the recovery solvent (5), and c% is the proportion of the paint resin (42) in the low-solid paint resin.

3. The process for secondary environmentally friendly recycling of waste solvents according to claim 2, characterized in that: The proportion of the paint resin (42) in the high-solid paint resin (6) is 40%, the proportion of the paint resin (42) in the recovery solvent (5) is 1%, and the proportion of the paint resin (42) in the low-solid paint resin is 30%.

4. The process for secondary environmentally friendly recycling of waste solvents according to claim 1, characterized in that: The step of filtering the waste solvent (4) of the enameled wire for particulate impurities to obtain the treated recovered solvent (5) containing the paint resin (42) comprises: coarse filtration and fine filtration; The coarse filtration comprises the steps of: using a circulation pump (11) to pump up the enameled wire waste solvent (4), passing through a filter core (12), intercepting large particles (41) whose size is greater than or equal to a first filter aperture, and obtaining the waste solvent after coarse filtration; The fine filtration comprises the steps of using a circulation pump (11) to evacuate the waste solvent after the coarse filtration, passing it through a filter bag (21), intercepting small particles (41) and flocs whose size is greater than or equal to a second filter aperture, and obtaining a processed recovered solvent (5) containing a paint resin (42), wherein the second filter aperture is smaller than the first filter aperture.

5. The process for secondary environmentally friendly recycling of waste solvents according to claim 4, characterized in that: During the coarse filtration and the fine filtration, the circulating filtration time is 4 hours respectively.

6. The process for secondary environmentally friendly recycling of waste solvents according to claim 1, characterized in that: The steps of mixing the high-solid paint resin (6) and the recovery solvent (5) into the cavity (32) according to the added amount, and using a circulation pump (11) to extract the high-solid paint resin (6) from the bottom of the cavity (32), and spraying the high-solid paint resin (6) from the top to the recovery solvent (5), so that the high-solid paint resin (6) is fully mixed with the recovery solvent (5) in the process of penetrating to the bottom, to form a low-solid paint resin that can be reused include: Pour the high-solid paint resin (6) into the bottom of the cavity (32) according to the added amount, and then pour the recovery solvent (5) onto the top of the high-solid paint resin (6); Inserting the feed port of the circulation pump (11) into the high-solid paint resin (6), and connecting a spray pipe group (31) to the discharge port of the circulation pump (11), wherein the spray port of the spray pipe group (31) is located above the cavity (32); After the circulation pump (11) extracts the high-solid paint resin (6) from the bottom of the chamber (32), it is sprayed from above to the recovery solvent (5) through the spray pipe group (31), so that the high-solid paint resin (6) is fully mixed with the recovery solvent (5) in the process of penetrating to the bottom, thereby forming a low-solid paint resin that can be reused.

7. A device for secondary environmentally friendly recycling of waste solvents, characterized in that: The device is applied to the process of any one of claims 1 to 6, and comprises: A filtering device is used to filter out particulate impurities from the waste solvent (4) of the enameled wire to obtain a processed recovered solvent (5) containing the paint resin (42); A calculation device is used for sampling the recovery solvent (5), obtaining the proportion of the paint resin (42) in the recovery solvent (5), and calculating the addition amount of the high-solid paint resin (6) according to the proportion of the paint resin (42); The processing device (3) is used to mix the high-solid paint resin (6) and the recovery solvent (5) into the cavity (32) according to the added amount, and use a circulation pump (11) to extract the high-solid paint resin (6) from the bottom of the cavity (32) and spray it on the recovery solvent (5) from the top, so that the high-solid paint resin (6) is fully mixed with the recovery solvent (5) in the process of penetrating to the bottom, so as to form a low-solid paint resin that can be reused.

8. The equipment for secondary environmentally friendly recycling of waste solvents according to claim 7, characterized in that: The filtering device comprises: A coarse filtering device (1) is used to filter the enameled wire waste solvent (4), intercept large particles (41) in the enameled wire waste solvent (4) whose size is greater than or equal to a first filtering aperture, and obtain the waste solvent after coarse filtration; The fine filtering device (2) is used to filter small particles (41) and floccules whose particle size is greater than or equal to the second filtering aperture to obtain a processed recovery solvent (5) containing a paint resin (42).

9. The equipment for secondary environmentally friendly recycling of waste solvents according to claim 8, characterized in that: The coarse filtering device (1) comprises at least a circulation pump (11) and a filter core (12) connected to the circulation pump (11); the filter core (12) is provided with a first filtering hole, and the aperture of the first filtering hole is the first filtering aperture; the fine filtering device (2) comprises at least a circulation pump (11) and a filter bag (21) connected to the circulation pump (11); the filter bag (21) is provided with a second filtering hole, and the aperture of the second filtering hole is the second filtering aperture.

10. The equipment for secondary environmentally friendly recycling of waste solvents according to claim 9, characterized in that: The processing device (3) comprises at least a chamber (32), a circulation pump (11) arranged in the chamber (32), and a spray pipe group (31) connected to the circulation pump (11), wherein the feed port of the circulation pump (11) extends into the bottom of the chamber (32), and the spray port of the spray pipe group (31) is located at the upper part of the chamber (32).

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